HZ=1000 ?

Emanuel Strobl emanuel.strobl at gmx.net
Tue Apr 5 02:09:07 PDT 2005

Am Dienstag, 5. April 2005 01:09 schrieb John Pettitt:
> cpghost at cordula.ws wrote:
> >Interestingly, HZ=100 has remained constant for decades (!), despite
> >CPUs getting faster all the time. This is an excellent value for most
> >typical usage patterns. Cranking it up should only be required for
> >special cases. Anyway, the HZ knob is there. Experiment with it until
> >you get optimal performance.
> In the dim and distant past (like 1983) some systems used HZ=50 or HZ=60
> depending on where in the world they were.   I used an MP/M based box
> that took it's clock tick from the power line (no good RTC hardware

Hmm, I've seen onboard RTCs which surely were less acurate than a 
power-line-driven oscillator was ;) Some RTCs are really bad. But at least 
here in germany power line frequency is astonishing acurate. We also have a 
broadcast station which generates it's 50Hz vertical refresh rate from a 
dedicated caesium clock. Of course this tv station is paid by the peoples....

Sorry, a bit OT, but I'm really impressed how constant power line frequency 


> available but the power company keeps pretty good time).
> John
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